Return of the emerald skull
(Junior Book)

Originally published: London: Doubleday

Barnaby Grimes is a tick-tock lad, running errands in his city, day and night, and high-stacking around the rooftops in search of new mysteries to solve. After collecting a strange parcel from a deserted ship and delivering it to the local schoolmaster, Barnaby soon realises that all is not well at the school.